Do pregnant women with depression have a pro-inflammatory profile?

Aim: We tested the hypothesis that maternal depression is associated with a pro-inflammatory state in pregnancy. Material and Methods: In this nested case-control study, pro-inflammatory cytokine levels were compared between women with depression in pregnancy (n = 100) and a computer-generated referent group of healthy women known not to be depressed (n = 100). We only included cases with a documented Diagnostic and Statistical Manual of Mental Disorders depression diagnosis in the current pregnancy. Serum samples drawn at 11-14 weeks of gestation were analyzed for levels of tumor necrosis factor-alpha and interleukin-6 using high-sensitivity immunoassays. Results: Maternal demographics were similar between the groups except for older age (34.1 vs 32.7 years, P = .05), and lower body mass index (27.3 vs 28.9 kg/m2, P = 0.03) among the depressed subjects. Compared to control women, tumor necrosis factor-alpha (5.8 3.4 vs 3.2 2.8 pg/ml, P < 0.0001) and interleukin-6 (2.4 3.8 vs 1.5 1.4 pg/ml, P = 0.03) levels were higher among women with depression. The higher rate of inflammatory cytokines remained significant after controlling for potential confounders, including maternal age and body mass index. Conclusion: Women with depression may have higher levels of inflammatory markers in early pregnancy. Our findings support the hypothesis that inflammation may be a mediator in the association between maternal depression and adverse perinatal outcomes.